Fix test_emcc_4 broken in #23995 (#24000)

Author: sbc100

Diff for: test/test_other.py

@@ -643,7 +643,7 @@ def test_emcc_4(self, compiler):
         # closure has not been run, we can do some additional checks. TODO: figure out how to do these even with closure
         assert '._main = ' not in generated, 'closure compiler should not have been run'
         if keep_debug:
-          self.assertContainedIf("assert(!Module['STACK_SIZE']", generated, opt_level == 0)
+          self.assertContainedIf("assert(typeof Module['STACK_SIZE'] == 'undefined'", generated, opt_level == 0)
         if 'WASM=0' in params:
           looks_unminified = ' = {}' in generated and ' = []' in generated
           looks_minified = '={}' in generated and '=[]' and ';var' in generated